I just had my first one on Sunday.
I actually had to cancel my original appointment due to unrelated illness so rebooked online using my reference number from my letter and was very surprised to see that it was mostly weekend appointments that were available - maybe they leave those free or something.
So I could select an appointment for when I hoped it might be quiet and went for 1340 hrs on Sunday. I also had various options for where I could get it done but went with the original venue as it was the closest and had parking. I don't know if it's the same throughout the UK of course, it may vary.
I got a lift there and put my mask on and just walked in. This place has automatic doors so no need to touch anything and there were arrows on the floor showing where to go and it was clearly marked and roped off in a one way system. Loads of hand sanitiser pumps dotted about too although I'd taken my own anyway.
I checked in with a very nice lady who was wearing a mask and behind a big clear plastic screen, she asked me my name, D.o.B. and my address then told me to take a seat in the waiting area and I would be called soon.
The waiting area was large and the seats were spaced well apart and there was only one other person waiting (also masked) and I sat several seats away from her.
I was called within a few minutes and went through to another very large area which was sectioned into separate booths along one side where I sat, they again checked my name, D.o.B and went through the info etc and confirmed that I was happy to go ahead and then they directed me over to another booth at the other side of the room where I got the vaccination and that was me done, I just had to follow the one way system back outside to freedom!
Oh, and they asked if I was driving and because I wasn't I got to leave straight away, I believe it's a 15 minute wait otherwise.